Hermetically enclosed refrigerating machine

ABSTRACT

The invention relates to a hermetically enclosed refrigeration compressor unit. The unit includes two sheet metal chambers for reducing the sound due to pressure effects. The sound reducing chambers are shallow in construction and have a common interior wall which extends upwardly between the cylinder and head of the compressor where it forms a part of the valving. Another wall of the sound reducing chambers also extends upwardly and forms a part of the cylinder head.

United States Patent [72] Inventors Bendt Wegge Romer Augustenborg; Lars Meisingset, Nordborg; Knud V. Valbjorn, Nordborg; Jorgen Dahlman Knudsen, Gjeslng pr. Esbjerg, all of,

Denmark [2]] Appl. No 23,083

[22] Filed June 3, 1969 [45] Patented Aug. 17, 1971 [73] Assignee Danfoss A/S Nordborg, Denmark [32] Priority Mar. 16, 1968 [33] I Germany [54] HERMETICALLY ENCLOSED REFRIGERATING MACHINE 1 l Claims, 4 Drawing Figs.

[52] U.S.Cl. 417/312 [511 lnLCl ..F04b39/00 [50] Field of Search 230/58, 232; 417/312 [56] References Cited UNITED STATES PATENTS Q HQ LBSQ 1/[958 Ilium: QlU/fill 3,480,206 I 1/1909 linemurk cl al 230/212 Primary Examiner-Robert M. Walker AttorneyWayne B. Easton ABSTRACT: The invention relates to a hermetically enclosed refrigeration compressor unit. The unit includes two sheet metal chambers for reducing the sound due to pressure effects. The sound reducing chambers are shallow in construction and have a common interior wall which extends upwardly between the cylinder and head of the compressor where it forms a part of the valving. Another wall of the sound reducing chambers also extends upwardly and forms a part of the cylinder head.

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SHEET 1 or 2 PATENTEU Aus1 nan SHEET 2 (IF 2 FIG 4 HERMETICALLY ENCLOSED REFRIGERATING. MACHINE The invention relates to a hermetically enclosed refrigerating machine having at least two chambers for reducing the sound due to pressure effects, which are formed of sheet metal shaped parts positioned one upon the other and which are secured to the cylinder by extending at least one of the sheet metal shaped parts.

In an earlier proposed construction, two sheet metal shaped parts, which include a thinner sheet extending between them, form the cylinder head, plus suction-valve chambers and the pressure-valve chamber, a first sound-reducing chamber being disposed at a distance below and a second sound-reducing chamber, again at a distance beneath. The pressure and suction-valve chambers are separated from each other by means of the thinner plate and throttling passages are formed along the length of the pressure pipe. Due to the mounting on the cylinder, such pressure reducing means is secured in a manner that is reliable and free from vibration. it can therefore also be accommodated in a relatively narrow gap between the case and the motor. Difficulties occur, however, if it is required further to increase the size of sound-reducing means consisting of two or more chambers, as would be required for reducing the frequency limits.

The object of the invention is to arrange, in a refrigerating machine of the above-mentioned kind, the two or more soundreducing chambers in such a way that the volume can be utilized in an optimum manner in sound-reducing means of prescribed exterior dimensions.

According to the invention, this object is achieved by the surfaces of the bases of the sound-reducing chambers lying one against the other and their heights at right angles thereto being small in relation to the dimensions of the surfaces. of the bases. g

The noise-reducing chambers are thus of extremely shallow construction and are positioned one directly upon the other. Their height is generally less than one-third of the smallest dimension of the surface of the base. The sum of the individual heights does not need to be greater than the height of noisereducing chambers that have been proposed in the past. Despite the small heights, a sufficiently large volume of chamber can be obtained because of the large base surface. The individual chambers completely fill the available space, in contrast to an arrangement wherein the chambers are formed in a vertical row between two sheet-metal shaped parts. space necessarily being sacrificed between the' sidewalls of the chambers.

In a refrigerating machine having a vertical shaft and a cylinder located at the top, it is expedient to position one of the noise-reducing chambers substantially below the cylinder head and another chamber substantially below the cylinder or its valve plate. Since appropriate space must be provided in the case between the cylinder and the cylinder head, the space therebelow is also available for the noise-reducing chambers.

If the plates of the stator pack are cut away for material-saving purposes, it is of advantage to position the noise-reducing chambers in the vicinity of the cutaway portion between the stator pack and the case.

A further simplification is achieved if two adjacent noisereducing chambers have a common middle plate which, together with a channel plate contiguous therewith, forms at least the throttle passages that have to be provided between the two noise-reducing chambers. The middle plate and the channel plate can here be covered on both sides by a cupshaped piece of sheet metal, so as to produce two shallow noise-reducing chambers on both sides of the middle plate.

It is also possible to extend the middle plate, the channel plate and the outer cup-shaped piece of sheet metal for the purpose of forming the cylinder head.

A further increase in volume is obtained by positioning the pressure-valve body made of strip, obliquely between two suction-valve chambers in the cylinder head and locating its fixing means below one of the suction-valve chambers, and by providing the outer noise-reducing chamber with an expanded portion beneath the other suction-valve chamber.

To enable the pressure pipe to be connected in a simple manner to the series-arranged noisemeducing chamber, the outer cup-shaped piece of metal may have a portion which lies flat on the middle plate and in which is inserted a pressure pipe the end of which extends into the inner sound-reducing chamber.

In a further form of the invention, two sheet-metal walls can be fitted on the outside of the two cupshaped pieces of sheetmetal, these walls being spaced away from the pieces of sheetmetal over practically their entire surfaces, a static gascushion being contained between them and the pieces of sheet-metal. This prevents the stream of suction gas and the sprayed oil from coming into contact with the surface of the sound-reduction means and dissipating heat which raises the temperature inside the case. Due to the good space-utilization, there is also room for these attached sheet-metal walls in the space available.

It is of advantage in the production of the component described if one of the sheet-metal shaped parts has bent over tabs at its edge, these acting as guide and fixing means when the sheet-metal shaped parts are fitted together. Here, the middle plates may have tabs which are bent over alternately to the two sides. The remaining sheet-metal shaped parts can have slots into which the tabs extend; the sheet-metal shaped parts so assembled are then soldered together in a soldering furnace, during which operation they are either held together by a mechanical device extending into the furnace from the outside or are temporarily fastened with the help of the tabs.

The invention will now be described in more detail by reference to embodiments illustrated in the drawing, wherein:

FIG. 1 is a view of a component according to the invention comprising noise-reducing chambers and the cylinder head,

FIG. 2 is a partial longitudinal section through a refrigerating machine of the invention on the line A-A of FIG. l,

FIG. 3 is a side elevation of the components of FIG. 1 seen from the outside, and

FIG. 4 is a front elevation of this component. A refrigerating machine is hermetically enclosed in a case shown in broken lines. A motor-carrying element 2 on the one hand comprises a cylinder bore 3 accommodating the piston 4 and on the other carries the stator pack 5 plus the stator winding 6 of the motor and the rotor 7 supported in a bearing, not illustrated. The otherwise circular stator plates in the pack 5 are cut away along the edge 8 to form a secant, to save material in known manner. A normal valve plate 9 is fitted at the front end of the cylinder chamber.

Attached to the valve plate is a component 10 which forms a cylinder head 1 1 and a sound-reducing means 12.

The sound-reducing means comprises two chambers 13 and 14 arranged one behind the other, these being interconnected by a throttle passage 15. The cylinder head 1 1 contains a pressure-valve chamber 16 and two suction-valve chambers 17 and 18, inlet openings of which can be seen in FIG. 1 and a side wall thereof in FIG. 2. Gas-cushion compartments 19 and 20 are provided outside the sound-reducing chambers 13 and M respectively.

A middle plate 21, together with a channel plate 22, forms straight-through passages and throttle passages 15. The soundreducing chamber 12 is formed with the help of an outer cupshaped piece 23 of sheet metal, and the sound-reducing chamber 14 is formed with the help of an inner cup-shaped piece 24 of sheet metal. Sheet metal walls 25 and 26, only the narrow edges of which bear against the pieces 23 and 24 of sheet metal, together with said pieces define gas-cushion compartments l9 and 20, and their lower ends may contain openings 27 through which refrigerant gas can enter the compartments.

The middle plate 6, the channel plate 22 and the outer cupshaped piece 23 of sheet metal are upwardly extended to form the cylinder head 11. The middle plate contains openings 28 and 29, which lead into the suction-valve chambers 17 and 18, and an opening 30, which leads into the pressure-valve chamber 16. The channel plate 22 separates the pressurevalve chamber and the suction-valve chambers. A pressurevalve member 31 made of strip, is obliquely arranged in the pressure-valve chamber in such a manner that its fixing means 32 is located beneath the suction-valve chamber 18. As shown in FIG. 3 the space beneath the other suction-valve chamber 17 is used for accommodating an expanded portion 33 of the noise-reducing chamber 13.

The suction gas is introduced into the suction-valve chambers 17 and 18 by way of openings in the valve plate 9, and is thence passed into the cylinder through the suction valve. The compressed gas emerging from the swept chamber passes through a pressure line portion 34, formed between the middle plate 21 on the one hand and the channel plate 22 and the piece 23 of sheet metal on the other hand, into the noisereducing chamber 13. Thence, the throttle passage 15 leads to an opening, not illustrated, in the middle plate 21 and on into the pressure-reducing chamber 14. At this point there is connected a pressure-line pipe 35 and for this purpose the sheet metal shaped parts 23 and 25 have an enlarged flat edge portion 36 through which the end of the pressure pipe 35 extends into the pressure chamber 14.

The two noise-reducing chambers 13 and 14 are very shallow in relation to the surfaces of their bases. They make optimal use of the volume available however.

For greater ease of assembly tabs 37 and 38 are provided at the edge of the middle plate 21, these being bent over alternately to the two sides. The other sheet metal shaped parts contain slots 39, complementary to these tabs. All the sheet metal shaped parts 26, 24, 22, 21, 23 and 25 can thus be easily assembled in the correct relationship to each other. By fastening the tabs or by means of a mechanical clamping device, the structure so obtained can be held in position and then passed through a furnace for the purpose of soldering.

We claim:

1. A hennetically enclosed refrigeration compressor unit comprising, a casing, a compressor in said casing having a cylinder and piston, a cylinder head forming a pressure valve chamber connected to said cylinder, two shallow sound reducing chambers connected to said pressure valve chamber, said sound reducing chambers having fluid passage means therebetween and a common wall, one of said sound reducing chambers being positioned below one end of said cylinder and the other of said sound reducing chambers being positioned below said cylinder head.

2. A hermetically enclosed refrigeration compressor unit according to claim 1 including a stator pack beneath said cylinder and adjacent said sound reducing chambers, said stator pack having a planar vertical surface adjacent said chambers.

3. A hermetically enclosed refrigeration compressor unit according to claim 1 including a plate in abutting engagement with said wall, said wall and said plate forming a throttle passage therebetween to provide fluid communication between said sound reducing chambers.

4. A hermetically enclosed refrigeration compressor unit according to claim 2 including a pair of inner and outer dish shaped members on opposite sides of said abutting wall and plate to form inner and outer ones of said sound reducing chambers.

5. A hermetically enclosed refrigeration compressor unit according to claim 4 wherein said plate, said wall and one of said dish shaped members extend in the direction of said cylinder and form said cylinder head.

6. A hermetically enclosed refrigeration compressor unit according to claim 2 wherein said head forms two suction valve chambers, a strip shaped valve positioned between said valve chambers, anchoring means for said strip shaped valve positioned between one of said suction valve chambers and one of said noise reducin chambers.

7. A hermetically enc osed refrigeration compressor umt according to claim 4 wherein said outer dish shaped member is between said casing and said plate, said outer member having a flat portion in abutting engagement with said plate, and a pressure pipe extending through said flat portion and into the interior of said inner one of said sound reducing chambers.

8. A hermetically enclosed refrigeration compressor unit according to claim 4 including inner and outer walls in respective spaced relation to said inner and outer dished shaped members to form a pair of static gas chambers on opposite sides of said sound reducing chambers.

9. A hermetically enclosed refrigeration compressor unit according to claim 8 in which said wall has a plurality of spaced assembly tabs on the periphery thereof, said tabs being engageable with the edges of said inner and outer walls for assembling said unit.

10. A hermetically enclosed refrigeration compressor unit according to claim 9 wherein said tabs are bent alternately to two sides.

11. A hermetically enclosed refrigeration compressor unit according to claim 9 wherein inner and outer walls have slots for receiving said tabs. 

1. A hermetically enclosed refrigeration compressor unit comprising, a casing, a compressor in said casing having a cylinder and piston, a cylinder head forming a pressure valve chamber connected to said cylinder, two shallow sound reducing chambers connected to said pressure valve chamber, said sound reducing chambers having fluid passage means therebetween and a common wall, one of said sound reducing chambers being positioned below one end of said cylinder and the other of said sound reducing chambers being positioned below said cylinder head.
 2. A hermetically enclosed refrigeration compressor unit according to claim 1 including a stator pack beneath said cylinder and adjacent said sound reducing chambers, saId stator pack having a planar vertical surface adjacent said chambers.
 3. A hermetically enclosed refrigeration compressor unit according to claim 1 including a plate in abutting engagement with said wall, said wall and said plate forming a throttle passage therebetween to provide fluid communication between said sound reducing chambers.
 4. A hermetically enclosed refrigeration compressor unit according to claim 2 including a pair of inner and outer dish shaped members on opposite sides of said abutting wall and plate to form inner and outer ones of said sound reducing chambers.
 5. A hermetically enclosed refrigeration compressor unit according to claim 4 wherein said plate, said wall and one of said dish shaped members extend in the direction of said cylinder and form said cylinder head.
 6. A hermetically enclosed refrigeration compressor unit according to claim 2 wherein said head forms two suction valve chambers, a strip shaped valve positioned between said valve chambers, anchoring means for said strip shaped valve positioned between one of said suction valve chambers and one of said noise reducing chambers.
 7. A hermetically enclosed refrigeration compressor unit according to claim 4 wherein said outer dish shaped member is between said casing and said plate, said outer member having a flat portion in abutting engagement with said plate, and a pressure pipe extending through said flat portion and into the interior of said inner one of said sound reducing chambers.
 8. A hermetically enclosed refrigeration compressor unit according to claim 4 including inner and outer walls in respective spaced relation to said inner and outer dished shaped members to form a pair of static gas chambers on opposite sides of said sound reducing chambers.
 9. A hermetically enclosed refrigeration compressor unit according to claim 8 in which said wall has a plurality of spaced assembly tabs on the periphery thereof, said tabs being engageable with the edges of said inner and outer walls for assembling said unit.
 10. A hermetically enclosed refrigeration compressor unit according to claim 9 wherein said tabs are bent alternately to two sides.
 11. A hermetically enclosed refrigeration compressor unit according to claim 9 wherein inner and outer walls have slots for receiving said tabs. 